Preparation of zwitterionic electron acceptors and donors

The reactions of 4, 4'-bipyridine and nicotinamide with 1, 3-propane sultone yields zwitterionic electron acceptors. Reaction of dimethylaminoethyl ferrocene with 1, 3-propane sultone yields a zwitterionic ferrocene electron donor. The electron acceptors and donor are reduced and oxidized to the respective radical anions and ferrocenyl cation. Dipropyl-4, 4'-bipyridinium disulfonate and the ferrocene derivative quench the excited Ru(bipy)₃²⁺.